yongboy/BigPipeDemoServlet.java

## BigPipeDemoServlet.java
/**
 * 模拟Facebook BigPipe异步展现页面
 * @author yongboy
 * @date 2011-2-21
 * @version 1.0
 */
@WebServlet(urlPatterns = "/bigPipeDemoServlet", asyncSupported = true)
public class BigPipeDemoServlet extends HttpServlet {
	private static final long serialVersionUID = 14526556595656565L;
	private static final Log log = LogFactory.getLog(BigPipeDemoServlet.class);
	private static final Executor executor;

	static {
		executor = Executors.newFixedThreadPool(500, new ThreadFactory() {
			public Thread newThread(Runnable r) {
				Thread thread = new Thread(r);
				thread.setName("BigPipe Thread " + thread.getId());
				thread.setPriority(Thread.MAX_PRIORITY);

				return thread;
			}
		});
	}

	protected void doGet(HttpServletRequest request,
			HttpServletResponse response) throws ServletException, IOException {
		response.setHeader("Connection", "Keep-Alive");
		response.setContentType("text/html;charset=UTF-8");
		response.setCharacterEncoding("UTF-8");

		PrintWriter out = response.getWriter();

		out.println(docType);
		out.println(headPart);
		out.println(bodyPart);

		out.flush();

		// 这里模拟把页面组件部分计算工作交由异步线程完成
		executor.execute(new AsyncRunnable(request.startAsync(request, response)));
	}

	/**
	 * 定义工作线程用于处理异步的内容输出
	 * @author yongboy
	 * @date 2011-2-21
	 * @version 1.0
	 */
	private static class AsyncRunnable implements Runnable {
		private final AsyncContext asyncContext;
		private int times = 1;

		public AsyncRunnable(final AsyncContext asyncContext) {
			this.asyncContext = asyncContext;
		}

		public void run() {
			try {
				// 设置超时为20s，系统默认超时时间为10s
				asyncContext.setTimeout(20L * 1000L);
				PrintWriter out = asyncContext.getResponse().getWriter();

				// 模拟按照页面组件重要程度按照顺序计算
				bussizeMethod(out, "header", "这里是主页LOGO区域");
				bussizeMethod(out, "left", genStrings("这里是内容文字",160, false ));
				bussizeMethod(out, "right", genStrings("肯德基在百事可乐杯子添加其他品牌可乐",41, true));
				bussizeMethod(out, "leftLeft", genStrings("肯德基在百事可乐杯子添加其他品牌可乐", 10, true));
				bussizeMethod(out, "leftRight", genStrings("肯德基在百事可乐杯子添加其他品牌可乐", 10, true));

				// 补齐页面标签
				outFinish(out);
			} catch (IOException e) {
				e.printStackTrace();
			}

			// 结束当前异步请求
			try{
				asyncContext.complete();
			}catch (Exception e) {
				// 可能因为出现超时（大于默认的超时时间10s）异常
				e.printStackTrace();
			}
		}

		private void bussizeMethod(PrintWriter writer, String id, String content){
			//模拟耗时
			try {
				Thread.sleep(1000 * (times++));
			} catch (InterruptedException e) {
				e.printStackTrace();
			}

			pagelet(writer, id, content);
		}

		private void pagelet(PrintWriter writer, String id, String content) {
			if (writer.checkError())
				return;
			writer.write("<script>" + "show(\"" + id + "\", \"" + content
					+ "\");" + "</script>\n");
			writer.flush();
		}

		private void outFinish(PrintWriter writer){
			if (writer.checkError())
				return;
			writer.println("</body>");
			writer.println("</html>");
			writer.flush();
			writer.close();
		}

		private String genStrings(String ori, int num, boolean line){
			if(num < 1)return ori;
			StringBuilder sb = new StringBuilder();

			for(int i=0; i < num; i++){
				sb.append(ori);
				if(line){
					sb.append("<br/>");
				}
			}

			return sb.toString();
		}
	}

	private static final String docType = "<!DOCTYPE html PUBLIC \"-//W3C//DTD XHTML 1.0 Transitional//EN\" \"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd\">";
	private static final String headPart = "<html xmlns=\"http://www.w3.org/1999/xhtml\">\n<head>\n"
			+ "<meta http-equiv=\"Content-Type\" content=\"text/html; charset=UTF-8\"/>\n"
			+ "<title>Bigpipe Demo</title>\n"
			+ "<link href=\"css/grid.css\" type=\"text/css\" rel=\"stylesheet\" media=\"screen\"/>\n"
			+ "<script type=\"text/javascript\">function show(id,text) { var b=document.getElementById(id); b.innerHTML = text; }</script>\n"
			+ "</head>";
	private static final String bodyPart = "<body>\n"
			+ "<div class='row'>\n"
			+ "<div class='column grid_12'><div class='container' id='header'>loading ...</div></div>\n"
			+ "</div>\n"

			+ "<div class='row'>\n"
			+ "	<div class='column grid_8'><div class='container' id='left'>loading ...</div>\n"
			+ "		<div class='row'>\n"
			+ "			<div class='column grid_4'><div class='container' id='leftLeft'>loading ...</div></div>\n"
			+ "		<div class='column grid_4'><div class='container' id='leftRight'>loading ...</div></div>\n"
			+ "	</div>\n"
			+ "	</div>\n"
			+ "	<div class='column grid_4'><div class='container' id='right'>loading ...</div></div>\n"
			+ "</div>";
}
	/**
	* 模拟Facebook BigPipe异步展现页面
	* @author yongboy
	* @date 2011-2-21
	* @version 1.0
	*/
	@WebServlet(urlPatterns = "/bigPipeDemoServlet", asyncSupported = true)
	public class BigPipeDemoServlet extends HttpServlet {
	private static final long serialVersionUID = 14526556595656565L;
	private static final Log log = LogFactory.getLog(BigPipeDemoServlet.class);
	private static final Executor executor;

	static {
	executor = Executors.newFixedThreadPool(500, new ThreadFactory() {
	public Thread newThread(Runnable r) {
	Thread thread = new Thread(r);
	thread.setName("BigPipe Thread " + thread.getId());
	thread.setPriority(Thread.MAX_PRIORITY);

	return thread;
	}
	});
	}

	protected void doGet(HttpServletRequest request,
	HttpServletResponse response) throws ServletException, IOException {
	response.setHeader("Connection", "Keep-Alive");
	response.setContentType("text/html;charset=UTF-8");
	response.setCharacterEncoding("UTF-8");

	PrintWriter out = response.getWriter();

	out.println(docType);
	out.println(headPart);
	out.println(bodyPart);

	out.flush();

	// 这里模拟把页面组件部分计算工作交由异步线程完成
	executor.execute(new AsyncRunnable(request.startAsync(request, response)));
	}

	/**
	* 定义工作线程用于处理异步的内容输出
	* @author yongboy
	* @date 2011-2-21
	* @version 1.0
	*/
	private static class AsyncRunnable implements Runnable {
	private final AsyncContext asyncContext;
	private int times = 1;

	public AsyncRunnable(final AsyncContext asyncContext) {
	this.asyncContext = asyncContext;
	}

	public void run() {
	try {
	// 设置超时为20s，系统默认超时时间为10s
	asyncContext.setTimeout(20L * 1000L);
	PrintWriter out = asyncContext.getResponse().getWriter();

	// 模拟按照页面组件重要程度按照顺序计算
	bussizeMethod(out, "header", "这里是主页LOGO区域");
	bussizeMethod(out, "left", genStrings("这里是内容文字",160, false ));
	bussizeMethod(out, "right", genStrings("肯德基在百事可乐杯子添加其他品牌可乐",41, true));
	bussizeMethod(out, "leftLeft", genStrings("肯德基在百事可乐杯子添加其他品牌可乐", 10, true));
	bussizeMethod(out, "leftRight", genStrings("肯德基在百事可乐杯子添加其他品牌可乐", 10, true));

	// 补齐页面标签
	outFinish(out);
	} catch (IOException e) {
	e.printStackTrace();
	}

	// 结束当前异步请求
	try{
	asyncContext.complete();
	}catch (Exception e) {
	// 可能因为出现超时（大于默认的超时时间10s）异常
	e.printStackTrace();
	}
	}

	private void bussizeMethod(PrintWriter writer, String id, String content){
	//模拟耗时
	try {
	Thread.sleep(1000 * (times++));
	} catch (InterruptedException e) {
	e.printStackTrace();
	}

	pagelet(writer, id, content);
	}

	private void pagelet(PrintWriter writer, String id, String content) {
	if (writer.checkError())
	return;
	writer.write("<script>" + "show(\"" + id + "\", \"" + content
	+ "\");" + "</script>\n");
	writer.flush();
	}

	private void outFinish(PrintWriter writer){
	if (writer.checkError())
	return;
	writer.println("</body>");
	writer.println("</html>");
	writer.flush();
	writer.close();
	}

	private String genStrings(String ori, int num, boolean line){
	if(num < 1)return ori;
	StringBuilder sb = new StringBuilder();

	for(int i=0; i < num; i++){
	sb.append(ori);
	if(line){
	sb.append("<br/>");
	}
	}

	return sb.toString();
	}
	}

	private static final String docType = "<!DOCTYPE html PUBLIC \"-//W3C//DTD XHTML 1.0 Transitional//EN\" \"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd\">";
	private static final String headPart = "<html xmlns=\"http://www.w3.org/1999/xhtml\">\n<head>\n"
	+ "<meta http-equiv=\"Content-Type\" content=\"text/html; charset=UTF-8\"/>\n"
	+ "<title>Bigpipe Demo</title>\n"
	+ "<link href=\"css/grid.css\" type=\"text/css\" rel=\"stylesheet\" media=\"screen\"/>\n"
	+ "<script type=\"text/javascript\">function show(id,text) { var b=document.getElementById(id); b.innerHTML = text; }</script>\n"
	+ "</head>";
	private static final String bodyPart = "<body>\n"
	+ "<div class='row'>\n"
	+ "<div class='column grid_12'><div class='container' id='header'>loading ...</div></div>\n"
	+ "</div>\n"

	+ "<div class='row'>\n"
	+ " <div class='column grid_8'><div class='container' id='left'>loading ...</div>\n"
	+ " <div class='row'>\n"
	+ " <div class='column grid_4'><div class='container' id='leftLeft'>loading ...</div></div>\n"
	+ " <div class='column grid_4'><div class='container' id='leftRight'>loading ...</div></div>\n"
	+ " </div>\n"
	+ " </div>\n"
	+ " <div class='column grid_4'><div class='container' id='right'>loading ...</div></div>\n"
	+ "</div>";
	}